It happens in the blink of an eye. One minute you're changing your baby's diaper and yearning for just a moment's peace, and the next moment you're preparing the guest bedroom for a visit from your now-adult child. How did that happen?

Your kids will always be your kids no matter if they're just learning to crawl, heading off for their first day of college or changing their own little one's diapers. But as your children get older, you no longer have to worry about making all of their decisions or setting boundaries to keep them safe. Of course, that doesn't mean you stop worrying about them.

"Once a parent always a parent and yet what the word ‘parent’ means shifts as kids mature and become adults," says Kathy Taberner, one-half of the mother/daughter team that founded the Institute of Curiosity, an organization that strives to help families navigate difficult conversations.

As your kids mature, your relationship with them needs to mature as well. Here are tips for having a great relationship with your adult children.

Listen

A 2014 poll of young adults from researchers at Clark University in Massachusetts found that young adults today stay in frequent contact with their parents, with 37 percent of 25- to 39-year-olds talking to their parents at least once a day and 85 percent checking in once a week. "Even after they no longer rely on their parents for financial support, parents remain among the most important people in the emotional lives of established adults,” says Clark University research professor of psychology and poll director Dr. Jeffrey Jensen Arnett.

As your children become adults, what they need from you more than anything is emotional support. So be prepared to listen and to share in the experiences of their lives.

Show some respect

Mom and her adult son The rules of parenting change as kids grow up and start leading their own lives. (Photo: PhotoMediaGroup/Shutterstock)

"Although parents still want to be part of their children’s lives, they also need to know how to support them so they show they believe in their kids," says Taberner.

When your kids were little, you may have grown accustomed to having the final word in any disagreements you have with your child. But now that they're all grown up, it's more important than ever to show your kids that you respect their viewpoint — even when you don't agree.

Accept their partners

This may be the toughest thing you ever have to do as a parent. If your child is lucky enough to find a partner with whom to share his life, it's likely he now will turn to that person for help in making big decisions, handling conflicts or sharing good news. It can be hard to move to the backseat when you spent so many years as the driver in your child's life. Sure, you may wish that your child's partner had a better job, spent less time at work or had fewer tattoos, but your job is to keep those opinions to yourself and love and support your child as he moves on to this phase of his life.

"The one exception is when you believe they are in peril, for example a substance problem or an abusive boyfriend or girlfriend," says Arnett. "Then you need to make your opinion and advice known, whether they like it or not (and they probably will not). It may not do much good, but you have to do what you can," he added.

Keep your opinions to yourself

When you spend the first years of your child's life making decisions for her about what clothes she should wear, what foods she should eat and what activities will fill her day, it can be difficult to break away from that role. But as Susan Groner, The Parenting Mentor, points out, "the major difference between parenting young children and adult children is that you should no longer be telling your kids what to do or even offering suggestions as to what they should do and/or how they should do it."

The last thing adult children want to hear from their parents is anything even bordering on judgement, so "no unsolicited advice!" says Groner.

Find new ways to connect

When your kids were little, you had complete control over family activities. But now that your children are older, you need to take cues from them to find new ways to connect and communicate. You certainly don't have to pretend to like bungee jumping, vegan-fusion cooking or their favorite band if you truly don't. In fact, your new experiences can be as simple as regular dinners at a favorite restaurant.

But hey, if you're up for it, now is a good time to step out of your comfort zone to try different experiences and find new ways to bond with your children. So maybe sign up for that 5K or Tae Kwan Do class together. You never know what might happen!